The mass leaking of GCHQ intelligence files has put the lives of British
soldiers at risk, former military leaders have warned.

The Edward Snowden exposes in the Guardian have caused “widespread concern in the military community” that it will give the advantage to the enemy on battlefields around the world.

The UK National Defence Association, which includes former senior military chiefs, said the newspaper had “crossed the line” between legitimate journalism and national security.

Serving soldiers on the ground, including those in Afghanistan, are also believe they are at more risk since the stories emerged, the Daily Telegraph has been told.

Earlier this week Andrew Parker, the director general of MI5, said the leaks had handed a “gift” to terrorists and put lives at risk.

General Sir Mike Jackson, former Chief of the General Staff, said: “I agree with everything Andrew Parker said.

“I think we are getting in to very dangerous territory here.”

Andy Smith, director of the UKNDA, said: “There is a fine line between pursuing a news story that might be embarrassing or inconvenient to a government – which is a legitimate journalistic endeavour – and on the other hand encouraging the leaking by defence officials of information that, once in the public domain, could be harmful to the security of the realm.

“There is a widespread concern in the military community that the Guardian has crossed that line.

“Intelligence is being publicised that could give advantage to our enemies.

“Newspaper editors must behave responsibly and with additional caution where defence secrets, as opposed to political sensitivities, are concerned.”

It is feared the exposing of intelligence techniques, from the former CIA analyst contractor, will allow extremists and terrorists intent on targeting British troops overseas to know how to avoid detection.

"It comes down to trust," said a former captain who served in Northern Ireland and Sierra Leone. "As a soldier you have to trust in intelligence and if we can't obtain that intelligence because of leaks then that will put lives at risk."

"We're at a crossroads where the civilian believes everything should be more transparent. But for the soldier in the field it is about being one step ahead of the terrorist."

"What right does Snowden have to give away our intelligence secrets now?" said the captain who asked not to be identified for security reasons.